Introduction to ISDE
Lloyd Massengill
Institute for Space and Defense Electronics
Vanderbilt University
Nashville, Tennessee, USA, 37235
Vanderbilt University
Home of the Commodores
(and the Radiation Effects Research Group and ISDE)
Vanderbilt Engineering
 Located in Nashville, TN
 Private Institution
 ~11,000 students
Undergraduate: 6,532
Graduate/professional: 5,315
School of Engineering: 1,305
 Engineering, Arts &
Sciences, Medicine,
Nursing, Law, Business,
Education, Music, Divinity
 Degrees in 2007
Baccalaureate: 1,468
MS: 1,062
PhD: 498
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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Vanderbilt Radiation Effects Program
Vanderbilt Engineering
World’s largest university-based radiation effects program
Radiation Effects
Research (RER) Group
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30 graduate students
A few undergraduate students
Open access
Basic research and support of ISDE
engineering tasks
Training ground for rad-effects engineers
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DTRA 6.1 Kickoff – 5/08
Institute for Space and
Defense Electronics (ISDE)
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14 full time engineers
2 support staff
ITAR compliant
Support specific radiation effects engineering
needs in government and industry
10 faculty with extensive expertise in radiation-effects
Beowulf supercomputing cluster
Custom software codes
EDA tools from multiple commercial vendors
Multi-million $ aggregate annual funding
Test and characterization capabilities and partnerships
Massengill – ISDE Introduction
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DTRA-supported Grad Student “Product” Examples
Vanderbilt Engineering
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> 25 peer-reviewed publications in 2007 under DTRA/RHM support
 > 35 presentations in 2007 under DTRA/RHM support
 13 presentations accepted for IEEE NSREC 2008 with DTRA/RHM
credit line
 >8 DTRA-supported graduate student degrees awarded last two years
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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What is ISDE?
Vanderbilt Engineering
ISDE is a contract engineering unit of Vanderbilt University created to
bring world-class support of space and DoD mission needs through
radiation effects analysis and rad-hard design
ISDE brings several decades of “academic” resources/expertise and
“real-world” engineering to bear on system-driven needs
ISDE provides:
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Government and industry radiation-effects resource
Modeling and simulation: RHTCAD, RHEDA
Design support: radiation models, RHBD
Technology support: assessment, characterization
System support: systems engineering
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Flexible staffing driven by project needs
Faculty
Graduate students
Professional engineering staff
ISDE Particulars:
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Established as a unit of Vanderbilt University: 1 Jan 2003
Academic staff: 10 faculty / ~30 graduate students
Full-time engineering staff: 14
Support staff: 2
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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ISDE Capabilities
Vanderbilt Engineering
 Support the design and analysis of radiation-hardened electronics
 Supply radiation effects models, design tools, and simulation services
 Provide engineering services for technology insertion and transfer
 Develop radiation hardness assurance test methods
 Address system-specific problems related to radiation effects
 Provide training to the community
 Retain a radiation effect “SWAT” team
 Reality training for future radiation effects “experts” (aka grad students)
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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Sampling of Current Projects
Vanderbilt Engineering
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U.S. Navy Trident II Life Extension (Draper prime)
• Honeywell SOI-IV, TI BiCom 1.5, and Intersil EBHF technologies
DTRA Radiation Hardened Microelectronics
• IBM 9SF 90nm, TI 65 nm
DARPA/DTRA Radiation Hardened by Design (Boeing prime)
• IBM 8SF 130nm and 9SF 90 nm CMOS – Trusted Foundry
NASA Electronic Parts & Packaging Program (NASA/GSFC)
• IBM: 5HP, 8HP, 9SF 90nm, TI: 65 nm, 45 nm
NASA Extreme Environment Electronics (Ga Tech prime)
• IBM 5AM SiGe and BAE 150 nm CMOS
CREME Monte Carlo (NASA MSFC/RHESE)
Aging of Electronics (U.S. Navy DTO/Lockheed-Martin)
U.S. Air Force Minuteman Technology Readiness
BAE SEU-Hardened SRAMs (BAE prime)
SEE Charge Collection Signatures at 90nm (and below) (ANT/IBM prime)
Virtual Irradiation Simulator Development (Air Force/AEDC/PKP)
Integrated Multi-scale Modeling of Molecular Computing Devices (DOE)
Substrate Charge Collection Studies (MEMC)
CFDRC TCAD Tool Development (DTRA SBIR and NASA STTR)
Lynguent Compact Model Development (DTRA SBIR)
SEU Analysis (Medtronic)
GaN HEMT/amplifier simulation (Lockheed Martin)
Radiation Effects on Emerging Electronic Materials and Devices (AFOSR/MURI)
Design for Reliability Initiative for Future Technologies (AFOSR/MURI through
UCSB)
DTRA Basis Research Efforts (three 6-1 grants)
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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USN D5LE Modeling Activities
Vanderbilt Engineering
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AMS- Custom Development
PDK Development
EBHF – 5 Design-fab-eval cycles supported
SOI-IV – 5 Design-fab-eval cycles supported
Bicom 1.5 – 2 Design-fab-eval cycles supported
Digital
IBIS
Standard Cell library validation
SSI –SOI-IV & SOI-V
Discrete
Actives
Passives
New Electrical Model Creation
Magamp
Power MOSFET
Design Community Support (remote & local)
Bugzilla – over 90 bugs reported, analyzed, & closed
App-notes
Model inventory
Tutorials
Designer Interface meetings
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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USN D5LE Model Completion Summary
Vanderbilt Engineering
 937 model files tested/calibrated/delivered to NEPL database
 757 of these are ISDE custom developed and calibrated
 Over 100-million calibration simulations performed
 Significant support, training, design, simulation activities
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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USN D5LE Model Completion Summary
Vanderbilt Engineering
A few milestones:
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45 major model releases/updates since Jan 2006
Complete PDK radiation models for EBHF, SOI-IV, BiCom
Complete electrical, dose-rate, and degraded / corner models for all accepted program
parts
Degraded parameter guide and corner models released
PCIC macro, micro, design, simulation support – identified a feedback path design
enhancement to correct out-of-spec recovery time
Enhanced macro models to include high-fidelity transient response (based on user
request)
New MOSFET electrical models developed to the fill vendor gaps
Developed and designed 8 test chips for program model calibration and verification
Implemented an online community model support and feedback process
Model training and designer interface meetings
General ELDO training and aid
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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The Vandy to ISDE Connection
Vanderbilt Engineering
Vanderbilt has a comprehensive radiation effects analysis program to
support DOD and commercial needs
Physics investigations – NASA/GSFC, NASA/MSFC, AFOSR MURI, DTRA
6.1 support – Vandy academic
 Response mechanisms investigations – DTRA RHM, NASA, Navy support
– Vandy academic / ISDE
 RHBD development – DARPA RHBD and DTRA RHM support – ISDE
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DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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“Applied” Side of the Single Event Program
Vanderbilt Engineering
Through DTRA, DARPA, and NASA support, Vanderbilt has been investigating
single-event mechanisms, circuit responses, hardening techniques, and radhard design from submicron to sub-100nm IC technology nodes
General Observations:
 Moore’s law complicates the testing, simulation, and analysis of all radiation
effects, especially single-events and soft error-rates
 The 250nm technology node was a watershed for the microelectronics
reliability community (especially those ‘radiation-concerned’). At 100-nm scale:
Circuits that “should” be SEE hard are proving not to be
Commercial ICs are showing alarming vulnerabilities to ground-based SEE
environments
Unexpected SEE vulnerabilities (e.g. protons) have appeared
Why?
 Single events can no longer be considered localized, time-isolated, average
energy phenomena
 The ‘region of influence’ of an ion strike extends far beyond a single circuit ‘bit’
- spatially, logically, and temporally
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
12
“Applied” Side of the Single Event Program
Vanderbilt Engineering
Through DTRA, DARPA, and NASA support, Vanderbilt has been investigating
single-event mechanisms, circuit responses, hardening techniques, and radhard design from submicron to sub-100nm IC technology nodes
General Observations:
 Moore’s law complicates the testing, simulation, and analysis of all radiation
effects, especially single-events and soft error-rates
 The 250nm technology node was a watershed for the microelectronics
reliability community (especially those ‘radiation-concerned’). At 100-nm scale:
Circuits that “should” be SEE hard are proving not to be
Commercial ICs are showing alarming vulnerabilities to ground-based SEE
environments
Unexpected SEE vulnerabilities (e.g. protons) have appeared
Why?
 Single events can no longer be considered localized, time-isolated, average
energy phenomena
 The ‘region of influence’ of an ion strike extends far beyond a single circuit ‘bit’
- spatially, logically, and temporally
Heuristic approaches to IC hardening are failing
Failure (upset rate) predictions are failing
Comprehensive radiation effects modeling, incorporating a priori physics,
is an essential part of mission-critical
hardness assurance
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
13
Example of VU Basic Research to ISDE Application to
Community Tech Transfer:
A “Real World” Problem
Vanderbilt Engineering
DICE 9SF shift register SEU test data
1E-7
60deg, longitudinal to rails
2
-2
(cm
Section
Cross Cross
Section
(cm ))
1E-8
60deg, orthogonal to rails
1E-9
SF-1-0deg-1111
SF-1-0deg-0000
SF-1-0deg-1010
SF-1-0deg-1100
SF-3-0deg-1010
SF-3-60degA-1010
SF-3-60degB-1010
Weibull
SF-2-0deg-1010
1E-10
1E-11
0
20
40
60
80
100
120
140
2
(MeV/mg/cm ) 2)
LETLET
(MeV/mg/cm
 Baze broadbeam testing (Feb 07) revealed: 90nm RHBD DICE latches
are hyper-sensitive to longitudinal-axis angular SE strikes
 Upset saturated cross-sections approach unhardened designs
 Results do not follow conventional cos() charge collection rules
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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“Real World” Issue
Vanderbilt Engineering
Issue:
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Boeing RHBD Phase 1.5 90nm DICE V1 latch did not meet SEE on-orbit errorrate goals (< 1E-10 E/BD) based on broadbeam error data and CREME96 rate
calculations
Cause:
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Phase 1.5 TCAD research work identified charge sharing as error mechanism
Complication:
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CREME96 (and other space error-rate codes)
do not properly handle layout-dependent effects (e.g. charge sharing) and
can significantly mis-predict error rates (by orders of magnitude)
 Therefore: unclear if DICE V1 or V2 on-orbit error rates, calculated for RHBD,
are accurate or dubious predictions
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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Resolution Strategy
Vanderbilt Engineering
VU “basic research” tools:
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Vanderbilt-ISDE has performed comprehensive TCAD analysis of SEE
mechanisms in sub-100nm technologies:
uncovered the importance of charge sharing
identified critical circuit node pairs
(supported in part by DTRA/RHM, DARPA RHBD, NRL Albany Nanotech)
 Vanderbilt-ISDE has developed a Monte-Carlo-based error-rate modeling
technique that
operates from first principles physics for ion energy deposition – “virtual irradiation”
does not apply conventional error-rate assumptions
(supported in part by NASA/GSFC and DTRA)
Task Plan:
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Vanderbilt-ISDE was asked by the RHBD program to apply this technique to the
Phase 1.5 90nm DICE V2 latch in order to calculate a more accurate on-orbit
error-rate expectation
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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Mixed-Mode TCAD DICE Setup
Vanderbilt Engineering
 Calibrated 620/80 PMOS devices constructed in TCAD using ISDE physical
description of the IBM 9SF FEOL technology
 Calibrated 280/80 NMOS BSIM3 devices constructed in DESSIS-SPICE for
pull-down loading
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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MRED Solid Modeling Component Setup
Vanderbilt Engineering
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The solid model serves as the foundation for the radiation transport and
calorimetry component of the analysis
 Use GDSII layout information to generate an extruded model of the 9SF Latch
 Each layer is assigned an accurate compositional description – chemical
stoichiometry and density
Substrate, Active, and Poly
Only
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
Substrate, Metallization,
and Passivation Shown
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MRED/SPICE Interface
Vanderbilt Engineering
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This project required the first application of the MRED-Spice coupling
concept.
 For each particle that strikes a sensitive volume, a Spice simulation is
launched.
 Each transistor’s collected charge is converted to a current pulse and
directed to the appropriate node during run-time.
TX1
MRED Eventj
Q(TXij)
Irradiate FF1 at a random time and
watch for an upset clocked out of FF2.
This process was repeated over
100,000 times for the final simulation
set.
DTRA 6.1 Kickoff – 5/08
SPICE
(Circuit Template)
%I1
%I2
%I..
%In
TX2
.
.
TXn
D
CLK
Massengill – ISDE Introduction
D FF1
CLK
Q
D FF2 Q
CLK
Q
PRE
CLR
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Calibration to Broadbeam Data
-8
10
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10
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o
10
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10
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10
-7
10
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10
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2
10
Simulation (50 MHz)
Data (25<f<50 MHz)
Cross Section (cm /bit)
10
-7
2
Cross Section (cm /bit)
Vanderbilt Engineering
o
Simulation 60 Tilt, 0 Roll
o
o
Experiment 60 Tilt, 0 Roll
o
o
Simulation 60 Tilt, 90 Roll
o
o
Experiment 60 Tilt, 90 Roll
0
10
20
30
40
50
60
70
10
-10
10
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10
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Simulation (50 MHz)
Data (25<f<50 MHz)
o
0
10
2
DTRA 6.1 Kickoff – 5/08
20
30
40
50
60
70
2
LET (MeVcm /mg)
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o
Simulation 0 Tilt, 0 Roll
o
o
Experiment 0 Tilt, 0 Roll
LET (MeVcm /mg)
Best agreement between model and experiment is
with the highest cross sections and lowest LET –
rate dominating
Massengill – ISDE Introduction
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SEU Rate Prediction
Vanderbilt Engineering
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To perform the rate prediction, the beam-calibrated model is modified to:
Mimic the isotropic environment and sample appropriately from each spectrum
(z=1,z=2,z=3,etc.)
Events are weighted to the relative abundance in the overall spectrum. This
methodology has been tested extensively and proven valid.
 The calculated rate is 1.7 +/- 0.2 x 10-8 error/bit-day
(the error bar is due to counting uncertainty only)
 Most errors occurred at grazing incidence ( >60 degrees )
 Began observing errors regularly around Z = 12 (Mg, max LET  10 MeVcm2/mg)
Tech Transfer:
 Based on Vandy analyses, improved V3 DICE latches have been designed
and fabbed by Boeing as part of the RHBD Phase 2.0 program
 Results on charge sharing, angular effects, well collapse, and MRED upset
rate modeling have been briefed to the community at NSREC, IRPS,
GOMAC…
DTRA 6.1 Kickoff – 5/08
Massengill – ISDE Introduction
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The “Big Picture”
Vanderbilt Engineering
Requirements
Radiation Aware Design
Rad-Aware
VHDL
Mixed-Signal
Functional Rad
Models
TCAD-Driven
Rad PDK
Models
On-Orbit
Error Rates
(Creme-MC)
Failure
Mechanisms
3D
Mixed-Mode
TCAD
Functional
Verification
Virtual Irradiation
Monte-Carlo
Virtual
Irradiation
First Principle
Radiation Physics
(MRED)
Device Design
/ Layout
Architecture
Verification
Library
Validation
Qualification Flow
Library Module
Design
Rad-Aware EDA
Simulation Enhanced Test
Design Flow
Functional
Design
Architecture
Design
Qualification
M&S Enabled ASIC D,T,&Q
Component
Response
Targeted Radiation Testing
for M&S Support
AAmulti-agency-funded
multi-agency-funded
development
developmenteffort
effortisisunderway
underway
to
tointegrate
integrateM&S
M&Sinto
intoD&Q
D&Q
DTRA 6.1 Kickoff – 5/08
Technology
Massengill – ISDE Introduction
Available
Under development
Future research
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